Market power is the most important determinant of liability in competition law cases throughout the world. Yet fundamental questions on the relevance of market power are underanalyzed, if examined at all: When and why should we inquire into market power? How much should we require? Should market...

The prohibition against price fixing is competition law’s most important and least controversial provision. Yet there is far less consensus than meets the eye on what constitutes price fixing, and prevalent understandings cannot be reconciled with principles of oligopoly theory. This article...

Economic analysis of competition regulation is most developed in the domain of horizontal mergers, and modern agency guidelines reflect a substantial consensus on the appropriate template for merger assessment. Nevertheless, official protocols are understood to rest on a problematic market...

This is a survey of the economic principles that underlie antitrust law and how those principles relate to competition policy. We address four core subject areas: market power, collusion, mergers between competitors, and monopolization. In each area, we select the most relevant portions of...

This is a survey of economic analysis of law, that is, of the emerging field under which the standard tools of microeconomics are employed to identify the effects of legal rules and their social desirability. Five basic subject areas are covered. The first is legal liability for harm. Here we...